import org.junit.jupiter.api.Test;

/**
 * @author Administrator
 * @date 2023/5/19 8:36
 */
public class test {
    @Test
    public static void main(String[] args) {
       String a="asdasdadad.jpg";
        String substring = a.substring(a.lastIndexOf("."));
        System.out.println(substring);
    }
}
